AMD Announces Radeon RX 5700 XT & RX 5700: The Next Gen of AMD Video Cards Starts on July 7th At $449/$379
by Ryan Smith on June 10, 2019 7:20 PM ESTA Quick Note on Architecture & Features
With pages upon pages of architectural documents still to get through in only a few hours, for today’s launch news I’m not going to have the time to go in depth on new features or the architecture. So I want to very briefly hit the high points on what the major features are, and also provide some answers to what are likely to be some common questions.
Starting with the architecture itself, one of the biggest changes for RDNA is the width of a wavefront, the fundamental group of work. GCN in all of its iterations was 64 threads wide, meaning 64 threads were bundled together into a single wavefront for execution. RDNA drops this to a native 32 threads wide. At the same time, AMD has expanded the width of their SIMDs from 16 slots to 32 (aka SIMD32), meaning the size of a wavefront now matches the SIMD size. This is one of AMD’s key architectural efficiency changes, as it helps them keep their SIMD slots occupied more often. It also means that a wavefront can be passed through the SIMDs in a single cycle, instead of over 4 cycles on GCN parts.
In terms of compute, there are not any notable feature changes here as far as gaming is concerned. How things work under the hood has changed dramatically at points, but from the perspective of a programmer, there aren’t really any new math operations here that are going to turn things on their head. RDNA of course supports Rapid Packed Math (Fast FP16), so programmers who make use of FP16 will get to enjoy those performance benefits.
With a single exception, there also aren’t any new graphics features. Navi does not include any hardware ray tracing support, nor does it support variable rate pixel shading. AMD is aware of the demands for these, and hardware support for ray tracing is in their roadmap for RDNA 2 (the architecture formally known as “Next Gen”). But none of that is present here.
The one exception to all of this is the primitive shader. Vega’s most infamous feature is back, and better still it’s enabled this time. The primitive shader is compiler controlled, and thanks to some hardware changes to make it more useful, it now makes sense for AMD to turn it on for gaming. Vega’s primitive shader, though fully hardware functional, was difficult to get a real-world performance boost from, and as a result AMD never exposed it on Vega.
Unique in consumer parts for the new 5700 series cards is support for PCI Express 4.0. Designed to go hand-in-hand with AMD’s Ryzen 3000 series CPUs, which are introducing support for the feature as well, PCIe 4.0 doubles the amount of bus bandwidth available to the card, rising from ~16GB/sec to ~32GB/sec. The real world performance implications of this are limited at this time, especially for a card in the 5700 series’ performance segment. But there are situations where it will be useful, particularly on the content creation side of matters.
Finally, AMD has partially updated their display controller. I say “partially” because while it’s technically an update, they aren’t bringing much new to the table. Notably, HDMI 2.1 support isn’t present – nor is more limited support for HDMI 2.1 Variable Rate Refresh. Instead, AMD’s display controller is a lot like Vega’s: DisplayPort 1.4 and HDMI 2.0b, including support for AMD’s proprietary Freesync-over-HDMI standard. So AMD does have variable rate capabilities for TVs, but it isn’t the HDMI standard’s own implementation.
The one notable change here is support for DisplayPort 1.4 Display Stream Compression. DSC, as implied by the name, compresses the image going out to the monitor to reduce the amount of bandwidth needed. This is important going forward for 4K@144Hz displays, as DP1.4 itself doesn’t provide enough bandwidth for them (leading to other workarounds such as NVIDIA’s 4:2:2 chroma subsampling on G-Sync HDR monitors). This is a feature we’ve talked off and on about for a while, and it’s taken some time for the tech to really get standardized and brought to a point where it’s viable in a consumer product.
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Phynaz - Monday, June 10, 2019 - link
AMD announces their GTX1080 competitor three years late.AshlayW - Monday, June 10, 2019 - link
RX Vega 64 launched a year after 1080, what are you talking about?Phynaz - Monday, June 10, 2019 - link
Vega wasn’t any competition as shown by sales.zinfamous - Monday, June 10, 2019 - link
garbage response is pure garbage. replaces performance argument with sales argument, thinking no one is paying attention. but we already know who you are.Phynaz - Monday, June 10, 2019 - link
Hahaha...Another AMD fanboy that can’t comprehend that Nvidia shipped this card three years ago today, and it used less power. How was the wait?Korguz - Monday, June 10, 2019 - link
zinfamous more like a garbage reply from and nvidia fanboy. as has been mentioned.. before final judgement is passed.. wait till these cards are reviewed by 3rd parties, and IMO.. its in every ones best interests, if these cards do perform as amd claims.. does any one want to keep paying nvidia's inflated prices for their cards ?? i sure has hell dont.. paying at best $500 bucks for an entry level 2060 card is not worth the upgrade of my current 1060. if this doesnt close the performance gap, then i think there arent many people that could be upgrading their current video cards.Drumsticks - Tuesday, June 11, 2019 - link
Er, I kind of want to see AMD succeed, but the 2060 is like $349 MSRP. If Nvidia prices are inflated, AMD sure isn't doing much to poke a hole in that bubble this time around. The 5700 is a little faster than the 2060 for $30 more, and the 5700XT is roughly equal to the 2070 for $50 less. They're both very vulnerable to price cuts or bundles from Nvidia right now.Korguz - Tuesday, June 11, 2019 - link
Drumsticks maybe in the US, but in other countries.. the prices are much higher... aka US $349, canada, $500 ( of the least expensive 2060 ) top of the line 2080ti is $2100, an RTX titan is $3500 !!!!!!!!!Phynaz - Tuesday, June 11, 2019 - link
People from other countries should stop complaining about the price of US tech if they can’t make their own. You Canucks should have kept ATI.Korguz - Tuesday, June 11, 2019 - link
phynaz, that comment right there shows how ignorant, and blind you really are... these prices are in US dollars, even if ati wasnt bought out, they would STILL list their prices in US dollars... where something is made.. has NO bearing on it being in US dollars.. these cards are made where? oh.. guess where.. asia... where do you think TSMC is ??